cpu_current_top_of_stack's initialization forgot about
TOP_OF_KERNEL_STACK_PADDING.  This bug didn't matter because the
idle threads never enter user mode.

Reviewed-by: Borislav Petkov <b...@suse.de>
Signed-off-by: Andy Lutomirski <l...@kernel.org>
---
 arch/x86/kernel/smpboot.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index ad59edd84de7..06c18fe1c09e 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -961,8 +961,7 @@ void common_cpu_up(unsigned int cpu, struct task_struct 
*idle)
 #ifdef CONFIG_X86_32
        /* Stack for startup_32 can be just as for start_secondary onwards */
        irq_ctx_init(cpu);
-       per_cpu(cpu_current_top_of_stack, cpu) =
-               (unsigned long)task_stack_page(idle) + THREAD_SIZE;
+       per_cpu(cpu_current_top_of_stack, cpu) = task_top_of_stack(idle);
 #else
        initial_gs = per_cpu_offset(cpu);
 #endif
-- 
2.13.6

Reply via email to